THURSDAY, June 20 (HealthDay News) -- A new test to help doctors identify the genotype of a person's hepatitis C infection has been approved by the U.S. Food and Drug Administration. The Abbott RealTime HCV Genotype II can distinguish between genotypes 1, 1a, 1b, 2, 3, 4, and 5, using an infected person's blood sample. Knowing the virus's genotype can help doctors determine the best treatment, the agency said Thursday in a news release. Hepatitis C is the most common chronic blood-borne infection in the United States, and the leading cause of liver transplant, the FDA said, citing the U.S. Centers for Disease Control and Prevention (CDC). Some 3.2 million people are infected with the virus, and about 15,000 people die from the infection every year. Untreated, hepatitis C can lead to liver cancer and liver failure, the agency warned. The virus is transmitted via blood and other bodily fluids, and intravenous drug users are at greatest risk of acquiring the infection. The new test is approved for people who are known to have the infection. It is not meant as a way to diagnose hepatitis C, or as a way to screen for the virus's presence in the blood, the FDA said. The test has not been evaluated in children or in people with compromised immune systems, the agency said. It is manufactured by Abbott Molecular, Inc., based in Des Plaines, Ill. More information The CDC has more about hepatitis C.